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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Análise dos efeitos de segunda ordem em pilares solicitados a flexão oblíqua composta. / Analysis of second order in the pillars requested by oblique bending composite.

Ceccon, Jorge Luiz 04 August 2008 (has links)
Na verificação do estado limite último das estruturas reticuladas em concreto armado se tem sempre os pilares solicitados à flexão oblíqua composta, seja devido a momentos fletores transmitidos pelas vigas ou lajes ou devido a imperfeições construtivas ou por ações normais ao eixo da peça comprimida, atuantes entre seus pontos de vinculação. Neste trabalho se está comparando os resultados que se obtém por dois processos de cálculo, quais sejam, a) Integração numérica com desacoplamentos das flexões nas duas direções principais de inércia com o uso da rigidez secante obtida de diagrama momento-curvatura, ou seja, os esforços de segunda ordem são calculados em cada direção como se não houvesse a solicitação de flexão na direção ortogonal e ao final se verifica a segurança da peça no Estado Limite Último considerando a flexão oblíqua composta; b) integração numérica considerando a flexão oblíqua composta com a curvatura obtida de diagrama momento-curvatura ponto a ponto já no cálculo dos efeitos de segunda ordem. Foram processados 215.740 pilares cuja análise conduz à conclusão de que se pode usar o procedimento citado no item (a) acima, com segurança e sem prejuízo da economia. / At check reticulated reinforced concrete structures in the ultimate limit state one always have the columns requested by a compression with biaxial bending , be due bending moments transmitted bay beams or slabs or due constructions imperfections or actions normal to the axis of the compressed piece acting between its points of attachment. This work is to compare the results that are obtained by two methods of calculation, which are: a) Numerical integration in each main direction of inertia with the use of secant stiffness obtained from bending-curvature diagram, it is, the second order efforts are calculated in each direction as if there was not request bending in the orthogonal direction and the end check the safety at ultimate limit state of the column by considering the biaxial bending; b) Numerical integration in each main direction of inertia with curvatures obtained point to point of moment-curvature diagrams, that consider the biaxial bending, to calculate the second order effects. Were processed 215.740 columns whose analysis leads to the conclusion that we can use the procedure mentioned in tem a) above, safely and without prejudice to the economy.
2

Análise dos efeitos de segunda ordem em pilares solicitados a flexão oblíqua composta. / Analysis of second order in the pillars requested by oblique bending composite.

Jorge Luiz Ceccon 04 August 2008 (has links)
Na verificação do estado limite último das estruturas reticuladas em concreto armado se tem sempre os pilares solicitados à flexão oblíqua composta, seja devido a momentos fletores transmitidos pelas vigas ou lajes ou devido a imperfeições construtivas ou por ações normais ao eixo da peça comprimida, atuantes entre seus pontos de vinculação. Neste trabalho se está comparando os resultados que se obtém por dois processos de cálculo, quais sejam, a) Integração numérica com desacoplamentos das flexões nas duas direções principais de inércia com o uso da rigidez secante obtida de diagrama momento-curvatura, ou seja, os esforços de segunda ordem são calculados em cada direção como se não houvesse a solicitação de flexão na direção ortogonal e ao final se verifica a segurança da peça no Estado Limite Último considerando a flexão oblíqua composta; b) integração numérica considerando a flexão oblíqua composta com a curvatura obtida de diagrama momento-curvatura ponto a ponto já no cálculo dos efeitos de segunda ordem. Foram processados 215.740 pilares cuja análise conduz à conclusão de que se pode usar o procedimento citado no item (a) acima, com segurança e sem prejuízo da economia. / At check reticulated reinforced concrete structures in the ultimate limit state one always have the columns requested by a compression with biaxial bending , be due bending moments transmitted bay beams or slabs or due constructions imperfections or actions normal to the axis of the compressed piece acting between its points of attachment. This work is to compare the results that are obtained by two methods of calculation, which are: a) Numerical integration in each main direction of inertia with the use of secant stiffness obtained from bending-curvature diagram, it is, the second order efforts are calculated in each direction as if there was not request bending in the orthogonal direction and the end check the safety at ultimate limit state of the column by considering the biaxial bending; b) Numerical integration in each main direction of inertia with curvatures obtained point to point of moment-curvature diagrams, that consider the biaxial bending, to calculate the second order effects. Were processed 215.740 columns whose analysis leads to the conclusion that we can use the procedure mentioned in tem a) above, safely and without prejudice to the economy.
3

Železobetonová nosná konstrukce / Reinforced concrete load-bearing construction

Eliášová, Kristýna January 2015 (has links)
My diploma thesis presents structural design of an apartment block in Praha Smíchov. It is a reinforced concrete column structure with six floors. Plane dimensions of the building are 19x36 m. The project includes design of main structural system elements - columns, ceiling plate, foundation and staircase structure.
4

Implementation Of Coupled Thermal And Structural Analysis Methods For Reinforced Concrete Structures

Albostan, Utku 01 February 2013 (has links) (PDF)
Temperature gradient causes volume change (elongation/shortening) in concrete structures. If the movement of the structure is restrained, significant stresses may occur on the structure. These stresses may be so significant that they can cause considerable cracking at structural components of large concrete structures. Thus, during the design of a concrete structure, the actual temperature gradient in the structure should be obtained in order to compute the stress distribution on the structure due to thermal effects. This study focuses on the implementation of a solution procedure for coupled thermal and structural analysis with finite element method for such structures. For this purpose, first transient heat transfer analysis algorithm is implemented to compute the thermal gradient occurring inside the concrete structures. Then, the output of the thermal analysis is combined with the linear static solution algorithm to compute stresses due to temperature gradient. Several, 2D and 3D, finite elements having both structural and thermal analysis capabilities are developed. The performances of each finite element are investigated. As a case study, the top floor of two L-shaped reinforced concrete parking structure and office building are analyzed. Both structures are subjected to heat convection at top face of the slabs as ambient condition. The bottom face of the slab of the parking structure has the same thermal conditions as the top face whereas in the office building the temperature inside the building is fixed to 20 degrees. The differences in the stress distribution of the slabs and the internal forces of the vertical structural members are discussed.
5

Železobetonová skeletová konstrukce nákupního centra / Reinforced concrete frame structure of shopping centre

Rajman, Martin January 2012 (has links)
The point of my diploma thesis was design elements of reinforced concrete frame structures mounted single – storey mall.I choose the most exposed to the specified longitudinal frame structure, where I assumed the most highly stressed elements, which I subsequently designed. All documents and calculations are illustrated in part B2 of my diploma thesis.
6

Improvements to wireless, passive sensors for monitoring conditions within reinforced concrete structures

Chou, Chih-Chieh 20 December 2010 (has links)
The corrosion of steel reinforcement in reinforced concrete structures constitutes an alarming problem. To combat this problem, researchers at the University of Texas at Austin developed two, low-cost, passive, wireless sensors: a threshold, corrosion sensor and an analog conductivity sensor. Today, the basic circuit designs for both sensors are finished and their reliabilities are confirmed. However, multiple problems regarding the durability of the sensors remain. This research project: (a) identifies these problems, (b) proposes enhancements for each type of passive, wireless sensor, (c) tests and evaluates the proposed modifications to the sensors, and (d) proposes potential improvements and areas of research regarding the future development of these two sensors. / text
7

CONTRIBUIÇÃO DOS PAINÉIS DE ALVENARIA NA ANÁLISE DE PÓRTICOS DE CONCRETO ARMADO / CONTRIBUTION OF MASONRY PANELS ON ANALYSIS OF REINFORCED CONCRETE FRAMES

Silva, Liriane Reis da 21 March 2014 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / In this paper, a study on masonry infilled reinforced concrete (RC) frames subjected to service limit state horizontal loads is presented, considering the masonry panel contribution in the stiffness of the structure. The analysis of infilled frames is performed in two ways: using the equivalent diagonal strut concept, called here as macromodelling and the finite element method (FEM) for the micromodelling. Due to simplicity, equivalent strut models are really attractive for the inclusion of masonry panels in structural models of buildings frames. However, formulations available in the literature provide substantially distinct values for determining the axial rigidity of the equivalent strut, and disregarding some important parameters of the structural behavior of the infilled frame. In the FEM analysis, numerical simulations of infilled RC frames are done, with and without openings, with different spans, stiffness of the columns and masonry properties, using finite elements type shell in the modeling, in addition to the consideration of the contact frame-masonry. The simulations results allow the assessment of the limitations of the existing formulations for determining the width of the diagonal strut. In infilled frames with openings of doors and windows, is evaluated how the size and position of the aperture affects the stiffness of the structure. Finally, the maximum stresses (tensile, compression and shear) of all models are evaluated and compared with their respective resistant stresses in order to determine the possibility of cracking of the masonry panels of frames subjected to service limit state actions. / Neste trabalho é apresentado um estudo sobre pórticos de concreto armado preenchidos com alvenaria submetidos a ações horizontais de Estado Limite de Serviço (ELS), considerando a contribuição do painel de preenchimento na rigidez da estrutura. A análise dos pórticos preenchidos é realizada de duas maneiras: empregando-se o conceito da diagonal equivalente, na denominada macromodelagem e o método dos elementos finitos (MEF) para a micromodelagem simplificada. Em razão da simplicidade, os modelos com barras diagonais equivalentes são bastante atrativos para a inclusão de painéis de alvenaria nos modelos estruturais de pórticos de edifícios. Entretanto, as formulações disponíveis na bibliografia especializada fornecem valores sensivelmente distintos para a determinação da rigidez axial da barra equivalente, além de desconsiderarem alguns parâmetros importantes do comportamento estrutural do conjunto pórtico-alvenaria. Na análise através do MEF são realizadas simulações numéricas de pórticos de concreto preenchidos com alvenaria, com e sem aberturas, com diferentes vãos, rigidez de pilares e propriedades da alvenaria, empregando-se elementos bidimensionais na modelagem, além da consideração do contato pórtico-parede. Os resultados dessas simulações permitem a avaliação das limitações das formulações existentes para a determinação da largura da barra equivalente. No caso de pórticos preenchidos com aberturas, é avaliado de que forma o tamanho e a posição da abertura afeta a rigidez da estrutura. Por fim, as máximas tensões solicitantes (tração, compressão e cisalhamento) de todos os modelos são avaliadas, e comparadas com as respectivas tensões resistentes, a fim de determinar a possibilidade de fissuração dos painéis de preenchimento de pórticos submetidos a ações de ELS.
8

Architektonická studie cyklistického stadionu /dráhy/ Favorit Brno /na volné ploše v Brně Komárově/. / Architectural study of the cycling stadium / runway / Favorit Brno / on the open space in.

Pappová, Martina January 2018 (has links)
The subject of the diploma thesis is an architectural study of a velodrome in Brno Komárov. It is an indoor cycling track which is still missing in the Czech Republic. The whole site of the Hněvkovského sports complex in Komárov was elaborated within the architectural study. The aim of the proposal was to attract a wide range of visitors to the site, so not only buildings for sports were designed. But also two sets of buildings as a modular construction from containers providing premises for rent. The construction of the velodrome was deign as a combination of monolithic reinforced concrete and steel truss structure. The cladding is design from insulated panel system.
9

Železobetonová konstrukce parkovacího domu / Reinforced concrete structure parking House

Mazura, Marek January 2019 (has links)
The diploma thesis deals with design of structural system of selected parts of load-bearing structure of car park – common floor slab, selected columns, staircase. The Finite Element Method software is used to analyse the load-bearing structure, the results are verified by simlyfied hand-done calculation. The design of structures is done according to valid standards.
10

Dětská léčebna se speleoterapií Ostrov u Macochy / Sanatorium with Speleotherapy for Childern Ostrov u Macochy

Rehák, Michal January 2015 (has links)
Designed children´s sanatorium is situated on the cadastral area of Ostrova u Macochy town, in the protected area of Moravsky Kras. The architecture of this building fits in the surroundings of the landscape and respects its features. The building main attributes are its south-facing slope, the compositional construction from prefabricated reinforced concrete structure and perimeter sandwich structure, as well as the massive insulation. Thanks to these characteristics, it is classified as energy-efficient building. These eight buildings, interconnected by the massive colonnade in its middle axis, force the user to take advantage of all its energy-efficient advantages.

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